package com.example.online_forum.Interceptor;

import com.example.online_forum.config.AppConfig;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
@Component
public class LoginInterceptor implements HandlerInterceptor {
    @Value("${online_forum.login.url}")
    private String defaultURL;
    /**
     * 前置处理：对请求的预处理
     * @return ture 继续执行流程 ,反之
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        HttpSession session = request.getSession(false);
        if(session != null && session.getAttribute(AppConfig.USER_SESSION) != null){
            //校验通过
            return true;
        }
        //校验URL是否正确
        if(!defaultURL.startsWith("/")){
            defaultURL = "/" + defaultURL;
        }
        //校验不通过,跳转到登录页面
        response.sendRedirect(defaultURL);
        return false;
    }
}
